Can't cycle the bolt with the rifle mounted

23 February 2010, 08:34

ramrod340

OK I've been shooting versions of the M98 for al ost 40 years. I have never had one that I normally tried to cycle the bolt while I kept the rifle mounted. Second shots were just not my norm.

Now the local guys have me shooting dangerous milk jugs and attacking targets for time. So having to dismount the rifle between rounds is slowing me down.

What I have is a MKX it isn't the quickloc and I have polished the cocking ramp. Is the factory bolt handle simply too short to give proper leverage? Is there something I've missing smoothing in the action? Or do I simply need to eat more Wheaties?

23 February 2010, 10:06

Blake 70

You have to cock that big mainspring in 60 degrees of bolt lift on that action. On a Mauser the same thing takes place in 90 degrees of rotation. Much greater mechanical advantage on the mauser.

23 February 2010, 10:11

ramrod340

quote:
On a Mauser the same thing takes place in 90 degrees of rotation

MKX as in Interarms Mark X commercial Mauser action.

23 February 2010, 10:11

JBrown

quote:
Originally posted by Blake 70:
You have to cock that big mainspring in 60 degrees of bolt lift on that action. On a Mauser the same thing takes place in 90 degrees of rotation. Much greater mechanical advantage on the mauser.

The Mark-X is a "Mauser".

Paul
How hard is the action to cycle when done at your side?

Jason

"You're not hard-core, unless you live hard-core."
_______________________

Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.

Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.

-Jason Brown

23 February 2010, 10:20

ramrod340

Jason not sure how to judge. It is harder than an old Military or 60 year old FN but not as hard as a MKX with the speedloc. But it appears close to about 15 other MKX I have around here. I seem to hit a hard spot at about 75-85% lift.

Thought I would take another look at the cocking ramp and cocking piece. Thought a differnet handle might help as well. I also need to check other rifles I have in the mounted position as well.

It's probably operator error.

23 February 2010, 10:44

N E 450 No2

Paul, try this.

Be sure that the area of the bolt that cocks the firing pin has some quality grease on it.

Also have some quality grease on the bolt lugs.

Then, think of the total bolt movement needed to reload the rifle to be in four Parts.

Part one, bolt handle UP. I make this up motion, in a quick snappy type movement.

Part two, bolt handle BACK. All the way BACK.

Part three, bolt handle FORWARD.

Part four, bold handle DOWN.

I grip the bolt knob by pinching the knob between my thumb and my trigger finger, my hand being in sort of a fist.

YOU DO NOT WANT YOUR LOWER FINGERS EXTENDED WHEN YOU CLOSE THE BOLT, AS ONE OF THEM MIGHT HIT THE TRIGGER.

I hold the rifle into my shoulder with my left hand [I am right handed] HARD, I also press my face into the stock HARD, when working the action.

It just takes some practice.

23 February 2010, 10:45

N E 450 No2

You might be trying to pull the bolt BACK before you have it all the way Up.

23 February 2010, 12:16

JBrown

quote:
Originally posted by ramrod340:
Jason not sure how to judge. It is harder than an old Military or 60 year old FN but not as hard as a MKX with the speedloc. But it appears close to about 15 other MKX I have around here. I seem to hit a hard spot at about 75-85% lift.

Funny, I went and tried my Mark-X and noticed that it is a bit "sticky" also. There is a world of difference between it any my FNs.

My Mark-X is not speedlock BTW.

quote:
Thought I would take another look at the cocking ramp and cocking piece.

You might try running one of your military(or FN) bolts through the Mark X receiver. Or you could switch out the cocking piece and spring and give it a try.

I kinda suspect the Mark X has a heavy spring, but I will have to investigate.

23 February 2010, 16:38

J.D.Steele

I lap the cocking cam & bolt ways, and the result is that the bolt handle can be lifted against its mainspring pressure with one finger. If the trigger is pulled while the bolt handle is being lowered, the pressure of the mainspring alone will cause the bolt handle to slam down into the locked position with an audible thump.

Won't ever be quite as slick as a good Krag but it's surprising just how much friction can be removed by a little lapping. Brownell's sells the garnet lapping paste.
Regards, Joe

23 February 2010, 19:07

Charles_Helm

What caliber? Mine are less likely to properly eject and feed from the shoulder. With a little less leverage in that position the empty brass hangs up on the rear bridge and gums up the works.

23 February 2010, 19:28

ramrod340

OK my before morning

testing indicated that the answer is "all of the above".

First when I swap this MKX spring with an fn it "feels" like a lighter bolt lift.

While It is polished it isn't lapped. The fn with a lot of miles on it wasn't noticable heavier with the MKX spring.

As I lift the MKX slowly there are several spots that feel rough the worst is the point where the cocking piecs slides over the corner from the ramp to the flat back of the bolt. Hope that made sense.

Last operator error. I paid attention to my lift and like N E 450 memtioned I believe I'm pulling backwards during the lift.

So since the fn didn't see a difference with the MKX spring it will stay there. The FN spring will be in the MKX. I will lap the ramp and cocking piece along with a little "gold" pistol lube. I also need to practice practice practice lifting not pulling as I lift.

Charles the cartridge is my 400PDK. Thanks to Too Manytools it feeds and ejects like $hit through a goose.

23 February 2010, 19:37

Tailgunner

Ramrod
One oft overlooked place for lube is on the primary extraction cam, IE where the front of the bolt lugs contact.
You can get a bit of a feel for that surface by stripping the bolt and pushing forward as you lift

23 February 2010, 19:47

ramrod340

Thanks Tailgunner. Another point I noticed was the extractor collar. There is far more effort required to rotate the extractor and collar on the MKX than the FN.

I just need to put a couple thousand miles on the action.

24 February 2010, 00:17

Blake 70

Sorry guys. Late at night and mistook an X for a V.

24 February 2010, 00:22

ramrod340

quote:
Late at night and mistook an X for a V

Figured that was the case. If this old fart could sleep he would have written it earlier in the evening.

24 February 2010, 07:11

Duane Wiebe

Just a thought about using trigger finger and thumb: This is an easy way to lose control of the bolt knob.

Remember the old days of stick shift (Three on the tree?") Use the little finger/palm to lift the bolt and pull all the way back...then rotate your palm so you're pushing the bolt forward with the palm, thumb guiding, bolt is driven home with the heel of the thumb/palm.

MUCH more mechanical advantage than using thumb and fore finger...also much more control.

Watch the Bi Athalon on the Olympics (If this is "alloweds" where you live) Total control of the bolt knob!

24 February 2010, 08:16

ramrod340

quote:
Remember the old days of stick shift (Three on the tree?") Use the little finger/palm to lift the bolt and pull all the way back...then rotate your palm so you're pushing the bolt forward with the palm, thumb guiding, bolt is driven home with the heel of the thumb/palm.

Yep Duane this old fart is a palm man. For the record I started on a 3 on the tree darn car lost 1st & 3rd so I drove it all winter with second and overdrive. Back when you never left town except to go park.

24 February 2010, 08:46

Abob

I had a van with column shift but my favorite car to drive was my Dad's convertible with "push button" shifting, think it was a Plymouth

24 February 2010, 09:02

Duane Wiebe

quote:
Originally posted by ramrod340:
quote:
Remember the old days of stick shift (Three on the tree?") Use the little finger/palm to lift the bolt and pull all the way back...then rotate your palm so you're pushing the bolt forward with the palm, thumb guiding, bolt is driven home with the heel of the thumb/palm.

Yep Duane this old fart is a palm man. For the record I started on a 3 on the tree darn car lost 1st & 3rd so I drove it all winter with second and overdrive. Back when you never left town except to go park.

Sounds like my 46 Ford...My dad made me overhaul the transmission....More than once...Thought about putting it back together with wing nuts!

24 February 2010, 13:04

Nordic2

Its a good exuse to get a tikka, no problems to use two fingers.

24 February 2010, 15:58

hawkins

Sometimes a heavy "Speed Spring" has been
added. That makes for a heavy boly lift.
Goodb Luck!

25 February 2010, 02:54

Oddbod

Get thee an SMLE

Problem solved.

26 February 2010, 00:37

ramrod340

Thanks to all the suggestions and observations. For now I'll pass on the Tikka and SMLE.

So what I have done.
1) Swapped spring with an old FN
2) Lapped the cocking piece and ramp
3) Lapped the extractor collar
4) Put a touch of Pro-cold on the cocking piece and bolt lugs.
5) cycled the bolt about 250 times.
6) Practice, practice practice

While I still need a lot of practice the bolt is now at least 100% easier to lift. Now the operator just needs to work on being fluid in his motion and build some muscle memory.